The UK's most complete GLP-1 guide
Every Question Answered. Every Side Effect Explained.
- How GLP-1 medications work
- Mounjaro vs Wegovy compared
- Injection instructions
- Side effects & solutions
- What to eat on treatment
- FAQs answered
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Who Manufactures Mounjaro and How to Access It in the UK
Mounjaro (tirzepatide) is manufactured by Eli Lilly and Company, a major US pharmaceutical manufacturer. In the UK, Mounjaro is available both through NHS specialist weight management services and via private prescription through online prescribers. Access routes, costs, and eligibility differ significantly between NHS and private pathways. Understanding who makes Mounjaro, how to access it, and what it costs can help you make an informed decision about whether this prescription-only medication is right for you.
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Calculate Your BMI Instantly
Enter your height and weight below. Supports both imperial (stone & lbs) and metric (kg). Results include NHS category, healthy weight range, and ethnicity adjustments.
What Is BMI and Why Does It Matter?
Body Mass Index (BMI) is the most widely used screening tool for assessing whether your weight falls within a healthy range. Used by the NHS, GPs, and weight management services across the UK, BMI provides a quick snapshot of your weight relative to your height. The formula is simple: your weight in kilograms divided by your height in metres squared (kg/m²).
While BMI isn't a perfect measure — it doesn't account for muscle mass, bone density, or fat distribution — it remains the standard first step in identifying potential weight-related health risks including type 2 diabetes, cardiovascular disease, high blood pressure, and certain cancers.
The NHS also recommends adjusted thresholds for people of South Asian, Chinese, or Black African heritage — a BMI of 23 or above is classified as overweight, and 27.5 as obese. Our calculator includes this adjustment as a one-click toggle.
Eli Lilly and UK Prescription Costs
Eli Lilly and Company manufactures Mounjaro (tirzepatide) at pharmaceutical facilities worldwide. Mounjaro was approved by the MHRA (UK Medicines and Healthcare products Regulatory Agency) for weight management in UK adults in 2023 and is subject to additional monitoring (Black Triangle ▼ status).
In the UK, Mounjaro costs vary significantly depending on your access route. Private prescription costs typically range from £129 to £320 per month, depending on your dose and the provider. The starting dose (2.5 mg) is usually the least expensive, whilst higher maintenance doses (10–15 mg) cost more. Costs include the pre-filled KwikPen device (four weeks' supply) plus the prescriber consultation fee. Most private providers charge between £40 and £150 for the initial consultation, with follow-up reviews costing £20–£80. These are estimates only — prices vary between providers and change regularly.
Clinically BackedWeight Loss
No appointments. No waiting rooms. Just care — from a UK-regulated online pharmacy.
How It Works
Three simple steps to understand your weight and take action.
Enter your height and weight in our free calculator. Get your BMI, NHS category, healthy weight range, and ethnicity-adjusted thresholds instantly.
If your BMI suggests you're overweight or obese, explore our GLP-1 calculators to project potential weight loss on Mounjaro or Wegovy.
Use our progress tracker to log your weight weekly, visualise your journey with charts, and stay motivated — all stored privately in your browser.
Free Weight Loss Tools & Guides
Everything you need to understand your weight, explore medication options, and track your progress — completely free.
NHS vs Private Access and Online Prescribing
NHS access: Mounjaro is approved for use within NHS tier 3 specialist weight management services, but availability is extremely limited and varies by region. You'll need a GP referral to a local specialist service, and waiting lists can be months or even years in many areas.
Private access: You can obtain a Mounjaro prescription from a UK-licensed prescriber via an online consultation without a GP referral. The process involves completing a health questionnaire, sometimes a video or phone consultation, and a prescriber decision. If approved, your prescription is sent to a GPhC-registered pharmacy for dispensing. Use our GLP-1 weight loss calculator to explore potential outcomes with tirzepatide at different doses.
NHS access: Mounjaro is approved for use within NHS tier 3 specialist weight management services, but availability is extremely limited and varies by region. You'll need a GP referral to a local specialist service, and waiting lists can be months or even years in many areas.
Private access: You can obtain a Mounjaro prescription from a UK-licensed prescriber via an online consultation without a GP referral. The process involves completing a health questionnaire, sometimes a video or phone consultation, and a prescriber decision. If approved, your prescription is sent to a GPhC-registered pharmacy for dispensing. Use our GLP-1 weight loss calculator to explore potential outcomes with tirzepatide at different doses.
- Dual GIP/GLP-1 receptor agonist
- Up to 22.5% body weight loss (SURMOUNT-1)
- Weekly injection, dose escalation over 20+ weeks
- Available via private prescription in the UK
- Doses: 2.5mg → 5mg → 7.5mg → 10mg → 12.5mg → 15mg
- GLP-1 receptor agonist
- Up to 15–17% body weight loss (STEP trials)
- Weekly injection, 5-step dose escalation
- NHS & private prescription available
- Doses: 0.25mg → 0.5mg → 1mg → 1.7mg → 2.4mg
Mounjaro vs Wegovy: Head-to-Head
A side-by-side comparison of the two most popular GLP-1 weight loss medications available in the UK.
| Feature | Mounjaro | Wegovy |
|---|---|---|
| Drug class | Dual GIP/GLP-1 agonist | GLP-1 agonist |
| Active ingredient | Tirzepatide | Semaglutide |
| Avg. weight loss | 15–22.5% | 12–17% |
| Key trial | SURMOUNT-1 (2022) | STEP 1 (2021) |
| Max dose | 15 mg weekly | 2.4 mg weekly |
| Escalation period | 20–32 weeks | 16–20 weeks |
| Administration | Weekly injection (pen) | Weekly injection (pen) |
| NHS availability | Private prescription only | NHS & private |
| Approx. private cost | £150–£250/month | £150–£300/month |
| Common side effects | Nausea, diarrhoea, constipation | Nausea, vomiting, diarrhoea |
Data sourced from SURMOUNT-1 and STEP 1 clinical trials. Costs are approximate and vary by provider. Always consult a prescriber.
Am I Eligible for Weight Loss Medication?
In the UK, eligibility for GLP-1 weight loss medications like Mounjaro and Wegovy is based on your BMI and overall health profile.
- BMI of 30 or above (obese)
- Age 18 or over
- No contraindicated conditions
- Committed to lifestyle changes
- BMI of 27 or above
- Plus type 2 diabetes
- Or high blood pressure
- Or obstructive sleep apnoea
Use our BMI calculator to check whether your BMI falls within the eligible range.
How We Built These Tools
Every calculator and guide on myweightcheck is built with accuracy and transparency in mind. Our BMI calculator uses the standard WHO formula with NHS-aligned category thresholds. Our GLP-1 projections are modelled on published clinical trial data from SURMOUNT and STEP studies.
All data stays on your device. We don't require sign-ups, and we don't store your health information on any server. Your progress tracker saves data locally in your browser using localStorage, so only you can see it.
We're based in the UK and our tools are designed specifically for UK users — supporting stone & lbs by default, referencing NHS guidelines, using NICE-approved medication data, and linking to GPhC-registered pharmacies.
Frequently Asked Questions
Common questions about BMI, weight loss medications, and our free UK tools.
Is Mounjaro available on the NHS in the UK?
Mounjaro is approved by NICE for use within NHS specialist (tier 3) weight management services. However, NHS availability is extremely limited and regional variation is significant. You'll need a GP referral and may face extended waiting lists. Private prescription routes are often more accessible and faster.
How much does Mounjaro cost privately in the UK?
Private Mounjaro costs typically range from £129 to £320 per month depending on dose. Initial consultations cost £40–£150, with follow-up reviews £20–£80. The starting dose (2.5 mg) is usually cheaper than maintenance doses (10–15 mg). Prices vary between providers.
What is Mounjaro, and how does it differ from Wegovy?
Both are prescription weight loss injections, but Mounjaro (tirzepatide) is made by Eli Lilly and works via a dual GIP and GLP-1 mechanism. Wegovy (semaglutide) is made by Novo Nordisk and uses a single GLP-1 mechanism. Mounjaro may produce slightly higher average weight loss in clinical trials, but individual results vary.
How do I get a private Mounjaro prescription in the UK?
You can apply via an online prescriber consultation without a GP referral. Complete a health questionnaire, undergo clinical assessment (sometimes via video or phone), and if approved, receive a prescription sent to a GPhC-registered pharmacy for dispensing. You'll pay for the consultation plus the medication cost.
Can I use my BMI to check if I'm eligible for Mounjaro?
Eligibility depends on BMI and health conditions. Generally, you may qualify if your BMI is 30 or above, or 27–29.9 with weight-related conditions like diabetes or hypertension. Use our free BMI calculator to check your BMI instantly, then discuss eligibility with a prescriber or your GP.
Ready to take control of your weight loss journey?
Start with a free BMI check, explore your GLP-1 options, or begin tracking your progress today. No sign-up. No cost. Just results.